> ## Documentation Index > Fetch the complete documentation index at: https://docs.budgetpixel.com/llms.txt > Use this file to discover all available pages before exploring further. # Classify a song's music genre > Classify one song into BudgetPixel's canonical music genre taxonomy — the same classifier that powers the site's music gallery. **Synchronous**: the response carries the genre plus style/mood tags and a confidence score. **Input**: one song (`audio`), max **20 MB** and **7 minutes**, as MP3, WAV, OGG, M4A, or FLAC. Accepts a public URL, an uploaded-file URL from [`POST /v1/uploads`](/api-reference/files/upload-input-media), a data URI, or raw base64. Tip: a 7-minute WAV exceeds 20 MB — use MP3 for long tracks. The classifier listens to a ~30-second excerpt sampled from ~25% into the track (the `clip` field in the response tells you the exact window). Only that excerpt is retained — privately, for ~1 day — never the full upload. **Pricing: flat 10 credits per song.** Estimate via [`POST /v1/cost`](/api-reference/models/estimate-the-cost-of-a-request) with `{"model": "music-genre"}`. Charged on success only — a classifier failure costs nothing. ## OpenAPI ````yaml /openapi.yaml post /classifications/music-genre openapi: 3.1.0 info: contact: email: support@budgetpixel.com name: BudgetPixel Support description: > The BudgetPixel developer API for programmatic image and video generation. Generation is **asynchronous**: you create a job, then poll its status until it reaches a terminal state (`succeeded` / `failed`). You are charged in credits only on success — never for failures, timeouts, or content blocked before generation. **Authentication.** All requests require an API key sent as a bearer token: Authorization: Bearer bpx_live_xxx Create and manage keys from your BudgetPixel account dashboard. The developer API is currently available on the **Ultra** plan. **Pricing.** API usage is metered in credits at each model's published price (see `GET /v1/models`). Consumer subscription perks (free daily generations, free-for-Ultra models, subscription discounts) do not apply to API traffic. title: BudgetPixel API version: '2026-06-20' servers: - description: Production url: https://api.budgetpixel.com/v1 security: - ApiKeyAuth: [] tags: - description: Account and credit balance name: Account - description: Discover available models and pricing name: Models - description: Upload input media for image/video generation name: Uploads - description: Image job status name: Images - description: FLUX image models name: Black Forest Labs - description: SeeDream image models name: Bytedance - description: Video job status name: Videos - description: Kuaishou Kling video models name: Kling - description: SeeDance video models name: ByteDance (SeeDance) - description: Music job status name: Audios - description: Music generation models name: Music - description: Format conversion for images, video, and audio name: Conversions - description: Publish posts to your BudgetPixel feed name: Social - description: Content moderation — NSFW rating and CSAM detection name: Moderation - description: Content classification — music genre detection name: Classification paths: /classifications/music-genre: post: tags: - Classification summary: Classify a song's music genre description: > Classify one song into BudgetPixel's canonical music genre taxonomy — the same classifier that powers the site's music gallery. **Synchronous**: the response carries the genre plus style/mood tags and a confidence score. **Input**: one song (`audio`), max **20 MB** and **7 minutes**, as MP3, WAV, OGG, M4A, or FLAC. Accepts a public URL, an uploaded-file URL from [`POST /v1/uploads`](/api-reference/files/upload-input-media), a data URI, or raw base64. Tip: a 7-minute WAV exceeds 20 MB — use MP3 for long tracks. The classifier listens to a ~30-second excerpt sampled from ~25% into the track (the `clip` field in the response tells you the exact window). Only that excerpt is retained — privately, for ~1 day — never the full upload. **Pricing: flat 10 credits per song.** Estimate via [`POST /v1/cost`](/api-reference/models/estimate-the-cost-of-a-request) with `{"model": "music-genre"}`. Charged on success only — a classifier failure costs nothing. operationId: classifyMusicGenre requestBody: content: application/json: schema: properties: audio: description: >- One song (public URL, uploaded-file URL, data URI, or raw base64). Max 20 MB and 7 minutes. MP3/WAV/OGG/M4A/FLAC. type: string required: - audio type: object required: true responses: '200': content: application/json: schema: properties: clip: description: The excerpt the classifier heard. properties: duration_seconds: type: number start_seconds: type: number type: object confidence: description: Classifier confidence, 0-1. type: number credits_charged: type: integer genre: description: >- Canonical genre, e.g. `Electronic & Dance`. One of the site's music genres. type: string genre_slug: description: URL-safe slug of the genre, e.g. `electronic-and-dance`. type: string id: description: Classification request id (audit reference). type: string mood: description: One short mood phrase. type: string tags: description: 3-6 style/mood/instrument tags. items: type: string type: array type: object description: The classification. '400': $ref: '#/components/responses/BadRequest' '401': $ref: '#/components/responses/Unauthorized' '402': content: application/json: schema: $ref: '#/components/schemas/Error' description: Insufficient credits. '429': $ref: '#/components/responses/TooManyRequests' components: responses: BadRequest: content: application/json: schema: $ref: '#/components/schemas/Error' description: The request was malformed or referenced an unavailable model. Unauthorized: content: application/json: schema: $ref: '#/components/schemas/Error' description: Missing or invalid API key. TooManyRequests: content: application/json: schema: $ref: '#/components/schemas/Error' description: Rate or queue limit reached. Retry after a short delay. schemas: Error: properties: error: properties: code: description: Stable machine-readable code. example: model_not_available type: string message: type: string type: description: Error category. example: invalid_request_error type: string required: - type - code - message type: object required: - error type: object securitySchemes: ApiKeyAuth: bearerFormat: bpx_live_* description: 'API key as a bearer token: Authorization: Bearer bpx_live_xxx' scheme: bearer type: http ````